Everything a drawn waveform is a function of. Two waveforms with equal specs are the same picture, so this is what the memo is keyed on. It is not a description of the waveform for anyone to read: it exists to be compared. `Config` is carried whole rather than picked apart because the drawing reads the font from it, and a field added there that the drawing then uses would otherwise silently stop invalidating the memo. Everything else is named individually because it is not all in one place.